Aerosol valve with pressure relief



United States Patent lnvcntor Joseph J. Shay Manchester, NH.

Appl. No 852,951

Filed Feb. 10, 1969 Patented Dec. 15,1970

Assignee Scovill Manufacturing Company Waterbury, Conn.

a corporation of Connecticut AEROSOL VALVE WITH PRESSURE RELIEF 5Claims, 5 Drawing Figs.

Int. Cl Fl6k 15/18 Field of Search 251/349,

353, 354; ZZZ/402.24, 402.22; 137/522, 348

[56] References Cited UNITED STATES PATENTS 1,707,660 4/1929 Hammerstein25 l/353X 2,008,574 7/1935 Bock 25 l/349X 2,551,688 5/1951 Metzler et al25l/353X 3,454,198 7/1969 Flynn 222/402.22X

Primary Examiner-M. Cary Nelson Assistant ExaminerMichael O. SturmAttorney-Dallett Hoopes ABSTRACT: An aerosol valve has a built-inpressure relief device, the valve being operable manually to spraythrough a nozzle in the usual manner, or automatically when thecontainer pressure exceeds a safe limit. A valve head seats by downwardpressure under the compressive force of a spring greater than the upwardforce of container pressure on the valve. For normal operation, thevalve is unseated by a tilt action to overcome the spring force.

AEROSOL VALVE WITH PRESSURE RELIEF The invention relates to aerosolvalves and the main objective is to obtain an excess pressure relieffunction without materially adding to the cost of the valve assembly.

Instead of a valve head seating by upward pressure against the seatunderside of a gasket, I utilize a valve closing downwardly against aseat around the inlet passage at the bottom of the valve body. A topgasket serves a sufiicient seal during operation to prevent passage ofmaterial around the stem. The valve is actuated only by tilt action toovercome the downward compressive force of a spring which must begreater than the fluid pressure actingupwardly on the valve. It does notopen by a vertical downward pressure and thus cannot be easily openedaccidentally when an actuator button is being pushed by down in placeafter the container is filled. A hollow valve stem projects from thevalve head to the outside of the container and the stern can be made-tofit a socket in an actuator button or it may have itself a socket toreceive the male portion of another type of actuator.

In the accompanying drawing, I have shown for purposes of illustration,one embodiment which the invention may serve in practice. In thedrawing:

FIG. I is a central vertical section of my improved valve mounted in anaerosol container cap;

FIG. 2 is a central section showing how the valve is operated duringmanual use;

FIG. 3 is a similar section showing the valve opening under excesscontainer pressure;

FIG. 4 is a partial cross section on line 4-4 of FIG. 1; and

FIG. 5 is a perspective view of the spring.

An aerosol can cap 6 has the usual rim 7 for securing it to thecontainer and a central pedestal constituting a housing 8. A valve body9 of cup-shape is secured in the housing 8 by indentations 10 engagingunder a shoulder 11 on the valve body. A nipple 12 extends downwardlyfrom the valve body 9 to accommodate a dip tube 13 and an inlet passage14 through this nipple continues through a boss 15 extending into thehollow portion of the valve body. A rubber like washer 16 is fittedaround this central boss 15 to provide a valve seat.

The valve itself has a head 17, a hollow stem 18 and a sealing lip orrim 19 adapted to seat against the washer 16 by downward pressure.

The top wall 20 of the housing 8 has an opening 21 which issubstantially larger than the cross-sectional area of stem 18 so thatthe stem is free to move a substantial amount in a lateral direction toallow tilting action around the lip 19 to unseat the valve, as shown inFIG. 2.

A top sealing gasket 22, also offlexible rubber like material, sealsagainst the inner surface of the top housing wall 20 and also around thevalve stem 18. The gasket 22 thus prevents leakage between the housing 8and the valve body 9 and also around the stem 18.

A spring which exerts the compressive force on the valve is mounted inthe valve body between the gasket 22 and valve head 17. It may bepossible to use a coil spring, but in view of the limited space. I haveshown a Belleville type spring generally indicated by the numeral 23. Ithas a collar 24 surrounding the valve stem 18 and bearing against thevalve head 17. Slots 25 extend from the collar through a rim section 26hearing against the gasket 22.

It will thus be seen that although the valve will not operate byvertical downward movement, it can be operated with a tilt action bypushing against the actuating button 27, as seen in FIG. 2. Thecontainer contents will then flow through the passage 14, around the lip19, through a flow aperture 28 in the wall of the valve stem 18 and outthrough the valve stem and the usual discharge orifice in the button 27.The flow aperture 28 must, of course, be located between the gasket 22and the head 17.

Within the sealing lip 19, a substantial area of the valve head, hereinindicated by the numeral 29, is continuously subjected to the pressureof the container contents to exert an upward pressure on the valve whichtends to unseat it.

23 15 so designed that its compressive force is The spring sufficientlygreater than the fluid pressure against the area 29 as to hold the valveseated under normal conditions. However, by properly proportioning thespring force and the area 29, this seal may be broken by internalpressure which exceeds any predetermined safe level so that the aerosolsolution is released before the can explodes.

My improved valve with its safety release feature utilizes a valve bodyand gasket combination which is generally like that of a well knownvalve as shown, for instance, in US. Pat. No. 3,158, 298 assigned to myassignee, having means to allow rapid pressure filling. Such meansincludes the passages 31 around the valve body.

I claim:

1. An aerosol valve assembly comprising:

a. a housing having an opening;

b. a valve body of cup-shaped secured in said housing and having a fluidinlet passage adapted to communicate with the interior of an aerosolcontainer;

c. a valve seat around said inlet passage;

d. a valve having a head adapted to close against said seat and having asubstantial area subjected to fluid pressure from said inlet passagetending to unseat the valve;

e. a hollow valve stem joined to said head and extending through saidopening in the housing, said stem being substantially smaller in crosssection than said opening so that it can move laterally; and

f. a sealing gasket bearing up against the inner surface of said housingaround said opening and also sealing around said stem, the wall of thestem having a flow aperture therethrough between said head and saidgasket;

. a spring urging a said valve down against said seat with apredetermined force greater than that normally exerted by the fluidpressure acting up on said valve head; and whereby said valve may beopened to permit flow through said stem either by a tilting forceapplied to the stem or by an unusually high fluid pressure in thecontainer.

2. An aerosol valve assembly as defined in claim 1 wherein said springbears downwardly against said head and upwardly against said sealinggasket.

3. An aerosol valve assembly as defined in claim 2 wherein said springis of conical shape having a collar surrounding the stem adjacent saidhead and a flat rim bearing against said sealing gasket.

4. An aerosol valve assembly as defined in claim 1 further characterizedby a boss surrounding said inlet passage and extending into said valvebody, said valve seat consisting of a rubber like boss and said headhaving asealing lip bearing against said washer, and wherein the area ofthe head within said lip is exposed to internal pressure of thecontainer through said inlet passage.

5. An aerosol valve assembly as defined in claim 1 wherein passage-waymeans are provided around the outer wall of said valve body to permitquick filling of the container by flow over the top of said gasket andaround said valve body.

